Endothelin concentrations in preterm infants treated with human recombinant erythropoietin

Background: Increased endothelin-1 (ET-1) production following recombinant erythropoietin (Epo) administration is a presumed etiology for the hyperten sion reported in some adults. It is unknown whether Epo has similar effects in preterm infants. Methods: Serum ET-1 and Epo concentrations were measur ed prior to study, and following the second and third doses in 20 preterm i nfants receiving intravenous (IV) or subcutaneous (SC) Epo. Blood pressures were monitored prior to Epo administration and during the first, second, a nd third dose. Results: Infants (963 +/- 54 g birth weight, 27.4 +/- 0.6 we eks gestational age, 18 +/- 3 days of life; mean +/- SEM) had baseline Epo concentrations of 5.5 +/- 1.3 mU/ml and ET-1 concentrations below the lower limits of detection (<1 pg/ml). Epo concentrations were 1,848 +/- 274 and 1,672 +/- 295 mU/ml following the second and third IV dose, respectively, w hile Epo concentrations were 420 +/- 92 and 290 +/- 35 mU/ml after the seco nd and third SC dose, respectively (p < 0.005, SC versus IV). ET-1 concentr ations remained below the limits of detection in all but 6 infants, whose c oncentrations were <3.3 pg/ml. Blood pressures did not increase above basel ine in either group during the study period. Conclusion: Despite the wide r ange of Epo concentrations measured, no correlation was observed between Ep o concentrations, ET-1 concentrations, and blood pressure during the 1-week study period. The long-term effects of Epo on ET-1 concentrations and bloo d pressure in preterm infants require further study. Copyright (C) 2000 S. Karger AG, Basel.